CN115138832A - Method for prolonging number of pure steel pouring furnaces based on molten steel weight information - Google Patents
Method for prolonging number of pure steel pouring furnaces based on molten steel weight information Download PDFInfo
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- CN115138832A CN115138832A CN202110333387.2A CN202110333387A CN115138832A CN 115138832 A CN115138832 A CN 115138832A CN 202110333387 A CN202110333387 A CN 202110333387A CN 115138832 A CN115138832 A CN 115138832A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 397
- 239000010959 steel Substances 0.000 title claims abstract description 397
- 238000000034 method Methods 0.000 title claims abstract description 30
- 230000000087 stabilizing effect Effects 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims description 66
- 238000009749 continuous casting Methods 0.000 claims description 15
- 238000005303 weighing Methods 0.000 claims description 15
- 238000005266 casting Methods 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 7
- 230000008569 process Effects 0.000 abstract description 12
- 230000003068 static effect Effects 0.000 description 20
- 238000004364 calculation method Methods 0.000 description 12
- 238000004519 manufacturing process Methods 0.000 description 9
- 239000011819 refractory material Substances 0.000 description 8
- 230000007423 decrease Effects 0.000 description 6
- 238000009628 steelmaking Methods 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 3
- 230000003628 erosive effect Effects 0.000 description 3
- 230000003139 buffering effect Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
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- 238000005516 engineering process Methods 0.000 description 1
- 238000004401 flow injection analysis Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
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- 230000002035 prolonged effect Effects 0.000 description 1
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- B22—CASTING; POWDER METALLURGY
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- B22D37/00—Controlling or regulating the pouring of molten metal from a casting melt-holding vessel
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Abstract
The invention discloses a method for prolonging the number of pure steel pouring furnaces based on weight information of molten steel, wherein the molten steel enters a tundish from a steel ladle through a steel ladle sliding plate, the steel ladle is fully filled with molten steel A, and the tundish is fully filled with molten steel B; 1. 1, ladle to ladle: 1) Opening the sliding plate when the molten steel ladle is larger than or equal to 90 percent A, increasing the opening degree, and ensuring that the molten steel tundish is stable at 90 percent B; 2) The molten steel of the steel ladle is reduced to 30-90 percent, the opening of the sliding plate is reduced, and the molten steel of the tundish is reduced and stabilized at 65-80 percent; 3) Reducing the steel ladle molten steel to 15-30 percent, and increasing the opening of the sliding plate until the tundish is full; 2. the pilot steel of the tundish after replacing the ladle is subjected to the control of the pilot steel at the plus or minus 50 percent, B to 70 percent; 3. replacing the ladle: 1) The opening of the sliding plate rises, and the molten steel in the tundish rises and is stabilized at 90 percent B; 2) Reducing the molten steel content of the steel ladle to 60-80%, reducing the opening of the slide plate to 40-50%, and reducing and stabilizing the molten steel content of the tundish to 65-80%; 3) Reducing the steel ladle molten steel to 15-30 percent, and increasing the opening of the sliding plate to 70-80 percent until the tundish is full; 4. and (5) replacing the steel ladles according to the set number of furnaces, and repeating the steps 2 and 3 until the whole pouring process is finished.
Description
Technical Field
The invention belongs to the field of continuous casting processes, and is mainly suitable for the field of tundish casting processes under the requirement of high steel purity in steel production; in particular to a method for prolonging the number of pure steel pouring furnaces based on weight information of molten steel.
Background
The high-grade steel has high requirements on the purity of steel, the steel-making process is a main process causing the fluctuation of the purity of steel, and the inclusion of the covering agent into the molten steel due to the reduction of the tonnage of the tundish is an important factor influencing the purity of steel in the steel-making process.
The tundish is an important tool for bearing the flowing and buffering of molten steel from a steel ladle to the crystallizer in the continuous casting process, and is also a key link for avoiding the influence on the purity of steel. Generally speaking, after the tonnage of molten steel in a tundish is reduced, the impact kinetic energy absorption and buffering action of molten steel in the tundish on the molten steel flow is weakened, and when the tonnage of the tundish is reduced to a critical value, the ladle flow injection recoil causes covering agent to be involved in the tundish and secondary oxidation of the molten steel causes steel purity to be influenced. Therefore, for the continuous casting production of pure steel, the tundish is required to be always in a full-tonnage state, namely the molten steel of the tundish is always in a higher tonnage, so that the pollution to the pure steel is avoided.
In actual pure steel production, the contradiction exists between the full ladle operation of the tundish and the number of continuous casting furnaces of the tundish, and two main problems exist: (1) when the tundish is constant at full tonnage, the covering agent continuously erodes the fixed positions of the refractory material of the working layer of the tundish and the refractory material of the long nozzle, and the number of continuous casting furnaces is reduced due to the serious erosion of the refractory material, (2) a plurality of ladle changing operations are carried out during continuous casting, at the moment, the tonnage of the tundish is reduced to a certain degree from the tonnage of the full ladle, the reduction amplitude depends on the length of ladle changing time, and the tonnage of the tundish is reduced to a critical value, so that the molten steel pollution is caused.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects in the prior art and provide a method for prolonging the number of pure steel pouring furnaces based on molten steel weight information, wherein the purity of steel is not polluted on the premise of ensuring the service life of a tundish.
The technical problem to be solved can be implemented by the following technical scheme.
A method for prolonging the number of pure steel pouring furnaces based on weight information of molten steel is characterized in that the molten steel enters a tundish from a steel ladle through a controlled steel ladle sliding plate and a long nozzle, and the weight of the molten steel when the steel ladle is fully filled is A, and the weight of the molten steel when the tundish is fully filled is B; the method is characterized by comprising the following steps:
(1) Control of the 1 st ladle
1) When the weight of the 1 st ladle of molten steel is ≧ 90 percent, opening the steel ladle sliding plate, and increasing the opening degree of the sliding plate from 0 percent to 70-80 percent, wherein the weight of the charged molten steel of the tundish is larger than that of the outflow molten steel, and the weight of the molten steel of the tundish is increased and stabilized at 90 percent B-B;
2) Reducing the weight of the molten steel in the ladle to 30-90% by A, reducing the opening of the slide plate of the ladle from 70-80% to 40-50%, wherein the weight of the charged molten steel in the tundish is less than that of the discharged molten steel, and reducing the weight of the molten steel in the tundish from 90-B to B, and stabilizing the weight of the molten steel in the tundish from 65-B to 80-B;
the preferred scheme is as follows: when the weight of the steel ladle molten steel is reduced to 55-75%, the opening of the steel ladle slide plate is reduced from 70-80% to 40-50%, the weight of the steel ladle filled in the tundish is less than that of the steel liquid flowing out, the weight of the steel liquid in the tundish is reduced from 90-B to B, and the steel ladle weight is stabilized at 75-B-80%;
3) When the weight of the molten steel in the ladle is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the molten steel in the tundish is increased to the full ladle weight B; when the weight of the steel ladle molten steel is reduced to 0 percent, the opening degree of the steel ladle sliding plate is reduced to 0 percent;
(2) Replacement ladle
Controlling the weight of the tundish steel liquid to be not less than 50% and B-70% when the ladle slide plate for replacing the ladle is opened;
(3) Take over control of the ladle
1) Opening a sliding plate of the steel ladle, and increasing the opening degree of the sliding plate from 0% to 70-80%, wherein the weight of the molten steel filled in the tundish is greater than that of the outflow molten steel, the weight of the molten steel in the tundish is increased and stabilized within 90 percent to B percent;
2) When the weight of the succeeding ladle steel liquid is reduced to 60-80 percent, the opening degree of the ladle slide plate is reduced from 70-80 percent to 40-50 percent, the weight of the tundish charging molten steel is less than that of the outflow molten steel, the weight of the molten steel in the tundish is reduced from 90 percent to B-80 percent, and the steel is stabilized at 65-80 percent to B-80 percent; the preferred scheme is as follows: reducing the weight of the molten steel in the ladle to 55-75% A, reducing the opening of the slide plate in the ladle from 70-80% to 40-50%, wherein the weight of the charged molten steel in the tundish is less than the weight of the discharged molten steel, and reducing the weight of the molten steel in the tundish from 90-B to B, and stabilizing the weight of the molten steel in the tundish at 75-B to 80-B;
3) When the weight of the steel ladle liquid is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the steel ladle liquid is increased to a full ladle weight B; when the weight of the steel ladle liquid is reduced to 0% A, the opening degree of the steel ladle slide is reduced to 0%;
(4) And (5) replacing a new ladle according to the set continuous casting furnace number, and repeating the steps (2) and (3) until the whole casting process is finished.
As a further improvement of the technical scheme, the packet changing time in the step (2) is controlled to be 2-4 min.
As one of the preferred embodiments of the invention, the real-time weight weighing information of the steel ladle molten steel is based on a weighing system arranged at a cantilever of a steel ladle rotary table.
Also as one of the preferred embodiments of the present invention, the real-time weight weighing information of the tundish molten steel is based on a weighing system installed at the frame of the tundish trolley.
And further, collecting and comparing real-time weight data of the steel ladle molten steel and the tundish molten steel by adopting an automatic control system, and controlling the opening of the corresponding steel ladle sliding plate.
The tundish pouring method for prolonging the number of pure steel continuous pouring furnaces is triggered by the weight change trend of steel ladles and molten steel of the tundish, automatically adjusts the tonnage change of the tundish according to the uniform erosion of refractory materials and the minimum tonnage guarantee principle of the tundish according to the change of the tonnage of the molten steel in the steel ladles, ensures the uniform erosion degree of the refractory materials of the tundish, simultaneously ensures that the tonnage of the tundish is always in a reasonable range through ladle change time optimization and the tonnage control of the molten steel of the tundish, namely forms a tundish pouring technology with steel purity not polluted on the premise of ensuring the service life of the tundish.
The scheme has the advantages that: the tonnage of the tundish can be kept at a higher level all the time, the pure molten steel is ensured not to be polluted, and meanwhile, the tonnage of the tundish is dynamically adjusted according to the tonnage change of the ladle, so that the corrosion of refractory materials of the tundish is relatively uniform, and the number of continuous casting furnaces of the tundish is prolonged.
Drawings
FIG. 1 is a schematic diagram of a system configuration module of the control method of the present invention;
FIG. 2 is a schematic view of a control curve of tonnage (weight) of molten steel in a tundish of the present invention;
FIG. 3 is a schematic view of the control flow of the ladle 1 according to the present invention;
in the figure: 1-ladle; 2-steel ladle sliding plate; 3- (ladle) long nozzle; 4-tundish.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
The invention provides a method for prolonging the number of pure steel pouring furnaces based on molten steel weight information, which comprises the following specific structure and control method:
the steel ladle rotary table cantilever and the tundish trolley frame are both required to be provided with a weighing system, and the weight data of the steel ladle and the tundish are transmitted to a basic automatic system (named as an L1 system) in real time through a data line.
Referring to fig. 1 to 3, a ladle 1 and a tundish 4 are connected through a long nozzle 3, and molten steel enters the tundish 4 from the ladle 1 through the long nozzle 3.
The L1 system is provided with a tundish tonnage calculation unit which is connected with a slide plate opening controller (for example, directly controlled by the opening and closing of a ladle slide plate 2 in the figure) and finally controls the change of the tundish molten steel tonnage.
The tonnage adjustment of the tundish is dynamically carried out based on the tonnage information of the steel ladle and the molten steel of the tundish, manual operation and intervention are not needed, and the condition that the working condition is unstable due to manual operation is avoided.
The tundish tonnage calculating unit receives the weight data of the steel ladle molten steel in the L1 system, and sends an instruction to the steel ladle slide plate controller according to the set static table of the relation between the weight of the steel ladle molten steel and the weight of the tundish molten steel, so as to adjust the opening of the steel ladle slide plate 2 and further adjust the tonnage of the tundish molten steel. And after the adjustment is finished, the tundish tonnage calculating unit receives tundish tonnage information feedback sent by the L1 system, if a preset target value is reached, the adjustment is finished, otherwise, secondary adjustment is carried out.
And (3) accumulating to form a static control table of steel ladle tonnage and tundish tonnage according to the test data, and controlling the pouring to start by taking the weight of the full ladle of steel liquid as A ton and the mass of the full ladle of steel liquid as B ton:
(1) when the weight of the 1 st ladle of steel ladle liquid is not less than A ton multiplied by 90 percent, the tundish tonnage calculation unit receives the weight data of the steel ladle liquid in the L1 system, and sends a request for adjusting the opening degree to a steel ladle slide plate controller according to the static table data, the opening degree of the slide plate is increased to 70-80 percent from 0 percent, and the tundish liquid is poured by B ton multiplied by 90 percent to B ton;
(2) when the weight of the steel ladle liquid = A ton multiplied by 30% -A ton multiplied by 90%, the tundish tonnage calculation unit receives the weight data of the steel ladle liquid in the L1 system, and sends a request for adjusting the opening degree to the steel ladle slide plate controller according to the static table data, the opening degree of the steel ladle slide plate is reduced from 70% -80% to 40% -50%, and the weight of the steel ladle liquid is reduced to B ton multiplied by 65% -B ton multiplied by 80%;
(3) when the weight of the steel ladle liquid is = A ton multiplied by 15% -A ton multiplied by 30%, the tundish tonnage calculation unit receives the weight data of the steel ladle liquid in the L1 system, and sends an opening adjustment request to the steel ladle slide plate controller according to the static table data, the opening of the steel ladle slide plate is increased from 40% -50% to 70% -80%, the weight of the steel ladle slide plate is increased to the full ladle weight of B ton, and when the weight of the steel ladle liquid is reduced to 0A, the opening of the slide plate is reduced to 0%.
The time interval between the closing of the steel ladle sliding plate before the ladle changing process and the opening of the steel ladle sliding plate → the opening of the steel ladle sliding plate is required to be 2-4 min, so that the tonnage of the molten steel of the tundish during the ladle changing process can meet the requirement of not less than B ton multiplied by 50% -B ton multiplied by 70%.
Then, the 2 nd ladle is cast, and the following control is carried out:
(1) the tundish tonnage calculating unit receives the full ladle weight information of the steel ladle liquid steel in the L1 system, the opening degree of the sliding plate is increased from 0% to 70-80%, and the tonnage of the tundish liquid steel is restored to B ton multiplied by 90% -B ton;
(2) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 60-A ton multiplied by 80 percent, the opening degree of the steel ladle sliding plate is reduced from 70-80 percent to 40-50 percent, and the weight of the tundish molten steel is reduced to B ton multiplied by 65-B ton multiplied by 80 percent;
(3) when the weight of the steel ladle liquid is reduced to A ton multiplied by 15 percent to A ton multiplied by 30 percent, the opening degree of the steel ladle sliding plate is increased from 40 percent to 50 percent to 70 percent to 80 percent, the weight of the middle ladle liquid is increased to the full ladle weight B ton multiplied by 100 percent, and when the weight of the steel ladle liquid is reduced to 0 percent, the opening degree of the sliding plate is reduced to 0 percent.
The subsequent continuous casting standard of the ladle is the same as the standard (referring to the casting control requirement of the ladle of the 2 nd ladle), wherein the ladle changing condition is the same as the above.
Wherein, fig. 3 is a control flow chart of the 1 st ladle, and the control flow of each successive ladle is similar to that.
The following are more specific examples based on the above-described scheme.
Example 1
7 furnaces are used for continuous casting in certain steelmaking production, and a travelling crane is used for hoisting the 1 st ladle to a ladle turret cantilever;
(1) the steel ladle weighing system measures that the weight of the full ladle molten steel of the steel ladle is A tons, the information is transmitted to a tundish tonnage calculating unit through an L1 system, a request for adjusting the opening degree is sent to a steel ladle sliding plate controller according to a static meter data calculating unit, the opening degree of the steel ladle sliding plate is increased from 0 percent to 70 percent, the tonnage of the tundish is increased, and the steel ladle is poured by B tons of the full ladle weight;
(2) when the weight of the steel ladle liquid steel is reduced to A ton multiplied by 70 percent, a tundish tonnage calculation unit receives the weight information of the steel ladle liquid steel in the L1 system, and sends a request for adjusting the opening degree to a steel ladle slide plate controller according to static table data, the opening degree of the steel ladle slide plate is reduced to 40 percent from 70 percent, and the weight of the steel ladle liquid steel is reduced to B ton multiplied by 65 percent;
(3) when the weight of the steel ladle liquid is reduced to A ton multiplied by 20 percent, the tundish tonnage calculating unit receives the weight data of the steel ladle liquid in the L1 system, and sends an opening adjusting request to the steel ladle slide plate controller according to the static table data, the opening of the steel ladle slide plate is increased from 40 percent to 72 percent, and the weight of the steel ladle liquid is increased to the full ladle weight of B ton. The weight of the steel ladle molten steel continuously decreases, when the steel ladle weighing system detects that the weight of the steel ladle full ladle molten steel is 0 percent A ton, the information is transmitted to a tundish tonnage calculation unit through an L1 system, an opening degree adjustment request is sent to a steel ladle sliding plate controller according to a static table data calculation unit, the opening degree of the steel ladle sliding plate decreases to 0 percent, the sliding plate is closed after the 1 st steel ladle pouring is finished, the 2 nd steel ladle is lifted to a rotary table cantilever by a crane to open the sliding plate for continuous pouring, and the closing-opening time of the steel ladle sliding plate is 2.5min before and after.
Casting the 2 nd ladle;
(1) the tundish tonnage calculating unit receives the information of the full ladle weight of the steel ladle liquid in the L1 system, requires to increase the opening degree of the steel ladle sliding plate, increases the opening degree of the steel ladle sliding plate from 0 percent to 70 percent, and restores the tonnage of the tundish liquid to B ton multiplied by 95 percent;
(2) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 80 percent, the opening degree of the steel ladle sliding plate is reduced from 70 percent to 40 percent, and the weight of the tundish molten steel is reduced to B ton multiplied by 70 percent;
(3) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 30 percent, the opening degree of the steel ladle sliding plate is increased from 40 percent to 75 percent, and the weight of the middle ladle molten steel is increased to the full ladle weight B ton multiplied by 100 percent. When the weight of the steel ladle liquid is reduced to A ton multiplied by 0%, the opening degree of the steel ladle sliding plate is reduced to 0%, the sliding plate is closed after the 2 nd steel ladle is poured, the pouring is finished, and the 3 rd steel ladle is lifted to the rotary table cantilever by the travelling crane to open the sliding plate for continuous pouring.
The continuous pouring requirements of the 3 rd ladle are the same as the above requirements until the seventh ladle finishes pouring, and the whole pouring process is finished.
According to the pouring process, the tonnage of the tundish is automatically adjusted under the control of the tonnage calculation unit of the tundish according to a static table, the tonnage of the tundish always fluctuates within a controllable range, the requirement of pure steel production on the critical tonnage of the tundish is met, the molten steel with high purity requirement is prevented from being polluted, the refractory of the tundish is uniformly eroded within a certain range, the refractory is not concentrated and continuously eroded at the fixed position of the refractory, and the number of the long continuous casting furnaces which can be expected is ensured.
Example 2
7 furnaces are used for continuous casting in certain steelmaking production, and a travelling crane is used for hoisting the 1 st ladle to a ladle turret cantilever;
(1) the steel ladle weighing system measures the weight of the full ladle steel liquid to be 95 percent A tons, the information is transmitted to a tundish tonnage calculating unit through an L1 system, a request for adjusting the opening degree is sent to a steel ladle slide plate controller according to a static table data calculating unit, the opening degree of the steel ladle slide plate is increased from 0 percent to 75 percent, the tonnage of the tundish is increased, and the steel ladle is poured by 95 percent B tons of the full ladle weight;
(2) when the weight of the steel ladle liquid is reduced to A ton multiplied by 30 percent, a tundish tonnage calculating unit receives the weight information of the steel ladle liquid in the L1 system, and sends an opening degree adjusting request to a steel ladle slide plate controller according to static table data, the opening degree of the steel ladle slide plate is reduced from 75 percent to 45 percent, and the weight of the steel ladle liquid is reduced to B ton multiplied by 70 percent;
(3) when the weight of the steel ladle liquid steel is reduced to A ton multiplied by 15 percent, the tundish tonnage calculation unit receives the weight data of the steel ladle liquid steel in the L1 system, and sends a request for adjusting the opening degree to the steel ladle slide plate controller according to the static table data, the opening degree of the steel ladle slide plate is increased from 45 percent to 75 percent, and the weight of the steel ladle liquid steel is increased to the full ladle weight of B ton multiplied by 100 percent. The weight of the steel ladle molten steel continuously decreases, when the steel ladle weighing system detects that the weight of the steel ladle full ladle molten steel is A ton multiplied by 0%, the information is transmitted to a tundish tonnage calculating unit through an L1 system, an opening degree adjusting request is sent to a steel ladle sliding plate controller according to static table data calculating unit, the opening degree of the steel ladle sliding plate decreases to 0%, the sliding plate is closed after the 1 st steel ladle pouring is finished, the 2 nd steel ladle is lifted to a rotary table cantilever by a travelling crane to open the sliding plate for continuous pouring, and the time spent on closing and opening the steel ladle sliding plate is 2.0min before and after the steel ladle sliding plate is lifted and lifted.
Casting the 2 nd ladle;
(1) the tundish tonnage calculating unit receives the information of the full ladle weight of the steel ladle liquid in the L1 system, requires to increase the opening degree of the steel ladle sliding plate, increases the opening degree of the steel ladle sliding plate from 0 percent to 75 percent, and restores the tonnage of the tundish liquid to B ton multiplied by 90 percent;
(2) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 80 percent, the opening degree of the steel ladle sliding plate is reduced from 70 percent to 40 percent, and the weight of the middle ladle molten steel is reduced to B ton multiplied by 70 percent;
(3) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 15 percent, the opening degree of the steel ladle slide plate is increased from 40 percent to 75 percent, and the weight of the middle ladle molten steel is increased to B ton multiplied by 100 percent. When the weight of the steel ladle molten steel is reduced to A ton multiplied by 0 percent, the opening degree of the steel ladle sliding plate is reduced to 0 percent, the sliding plate is closed after the 2 nd steel ladle pouring is finished, the pouring is finished, and the 3 rd steel ladle is lifted to the rotary table cantilever by the travelling crane to open the sliding plate for continuous pouring.
The continuous pouring requirements of the 3 rd ladle are the same as the above requirements until the seventh ladle finishes pouring, and the whole pouring process is finished.
According to the pouring process, the tonnage of the tundish is automatically adjusted under the control of the tonnage calculation unit of the tundish according to a static table, the tonnage of the tundish always fluctuates within a controllable range, the requirement of pure steel production on the critical tonnage of the tundish is met, the molten steel with high purity requirement is prevented from being polluted, refractory materials of the tundish are uniformly corroded within a certain range, the refractory materials are not concentrated and continuously corroded at fixed positions, and the number of furnaces for continuous pouring in a predictable way is ensured.
Example 3
7 furnaces are continuously cast in certain steelmaking production, and a travelling crane hoists the 1 st ladle to a ladle turret cantilever;
(1) the steel ladle weighing system measures the weight of the full ladle steel liquid to be 90 percent A tons, the information is transmitted to a tundish tonnage calculating unit through an L1 system, a request for adjusting the opening degree is sent to a steel ladle slide plate controller according to a static table data calculating unit, the opening degree of the steel ladle slide plate is increased from 0 percent to 80 percent, the tonnage of the tundish steel liquid is increased, and the steel ladle is poured by 90 percent B tons of the full ladle weight;
(2) when the weight of the steel ladle liquid is reduced to A ton multiplied by 85 percent, a tundish tonnage calculating unit receives the weight information of the steel ladle liquid in the L1 system, and sends an opening degree adjusting request to a steel ladle slide plate controller according to static table data, the opening degree of the steel ladle slide plate is reduced from 80 percent to 50 percent, and the weight of the steel ladle liquid is reduced to B ton multiplied by 80 percent;
(3) when the weight of the molten steel in the steel ladle is reduced to A ton multiplied by 30 percent, the tonnage calculation unit of the tundish receives the weight data of the molten steel in the steel ladle system L1, and sends a request for adjusting the opening degree to the controller of the steel ladle slide plate according to the data of the static table, the opening degree of the steel ladle slide plate is increased from 50 percent to 80 percent, and the weight of the molten steel in the tundish is increased to the weight of B ton multiplied by 100 percent. The weight of the steel ladle molten steel continuously decreases, when the steel ladle weighing system detects that the weight of the steel ladle molten steel is A ton multiplied by 0%, the information is transmitted to a tundish tonnage calculating unit through an L1 system, an opening degree adjusting request is sent to a steel ladle sliding plate controller according to static table data calculating unit, the opening degree of the steel ladle sliding plate decreases to 0%, the sliding plate is closed after the 1 st steel ladle pouring is finished, the 2 nd steel ladle is lifted to a rotary table cantilever by a travelling crane to open the sliding plate for continuous pouring, and the closing-opening time of the front steel ladle sliding plate and the rear steel ladle sliding plate is 4.0min.
Casting the 2 nd ladle;
(1) the tundish tonnage calculating unit receives the information of the full ladle weight of the steel ladle liquid in the L1 system, and requires to increase the opening of the steel ladle sliding plate, the opening of the steel ladle sliding plate is increased from 0% to 80%, and the tonnage of the tundish liquid is restored to B ton multiplied by 90%;
(2) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 80 percent, the opening degree of the steel ladle sliding plate is reduced from 70 percent to 40 percent, and the weight of the middle ladle molten steel is reduced to B ton multiplied by 70 percent;
(3) when the weight of the steel ladle molten steel is reduced to A ton multiplied by 15 percent, the opening degree of the steel ladle slide plate is increased from 40 percent to 75 percent, and the weight of the middle ladle molten steel is increased to B ton multiplied by 100 percent. When the weight of the steel ladle liquid is reduced to A ton multiplied by 0%, the opening degree of the steel ladle sliding plate is reduced to 0%, the sliding plate is closed after the 2 nd steel ladle is poured, the pouring is finished, and the 3 rd steel ladle is lifted to the rotary table cantilever by the travelling crane to open the sliding plate for continuous pouring.
The continuous pouring requirements of the 3 rd ladle are the same as the above, until the seventh ladle finishes pouring, and the whole pouring process is finished.
According to the pouring process, the tonnage of the tundish is automatically adjusted under the control of the tonnage calculation unit of the tundish according to a static table, the tonnage of the tundish always fluctuates within a controllable range, the requirement of pure steel production on the critical tonnage of the tundish is met, the molten steel with high purity requirement is prevented from being polluted, the refractory of the tundish is uniformly eroded within a certain range, the refractory is not concentrated and continuously eroded at the fixed position of the refractory, and the number of the long continuous casting furnaces which can be expected is ensured.
Claims (6)
1. A method for prolonging the number of pure steel pouring furnaces based on weight information of molten steel is characterized in that the molten steel enters a tundish from a steel ladle through a long nozzle through a controlled steel ladle sliding plate, the weight of the molten steel when the steel ladle is fully filled is taken as A, and the weight of the molten steel when the steel ladle is fully filled is taken as B; the method is characterized by comprising the following steps:
(1) Control of the 1 st ladle
1) When the weight of the 1 st ladle of molten steel is ≧ 90 percent, opening a ladle sliding plate, starting to increase the opening degree of the ladle sliding plate from 0 percent to 70-80 percent, enabling the weight of the molten steel filled in the tundish to be larger than the weight of the outflow molten steel, enabling the weight of the molten steel in the tundish to increase, and stabilizing the steel in 90 percent B-B;
2) Reducing the weight of the molten steel in the ladle to 30-90% by weight, reducing the opening of the slide plate in the ladle from 70-80% to 40-50%, reducing the weight of the molten steel charged in the tundish to less than the weight of the discharged molten steel, reducing the weight of the molten steel in the tundish from 90% by weight B-B, and stabilizing the steel in the ladle at 65-80% by weight B-B;
3) When the weight of the molten steel in the ladle is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the molten steel in the tundish is increased to the full ladle weight B; when the weight of the steel ladle liquid is reduced to 0 percent, the opening degree of the steel ladle slide plate is reduced to 0 percent;
(2) Replacement ladle
Controlling the weight of the tundish steel liquid to be not less than 50% and B-70% when the ladle slide plate for replacing the ladle is opened;
(3) Take over control of the ladle
1) Opening a steel ladle sliding plate, wherein the opening degree of the sliding plate is increased to 70-80% from 0%, the weight of the molten steel filled in the tundish is greater than that of the molten steel flowing out, the weight of the molten steel in the tundish is increased, and the molten steel in the tundish is stabilized at 90% B-B;
2) After the weight of the steel ladle liquid is reduced to 60-80% A, the opening of the steel ladle slide plate is reduced from 70-80% to 40-50%, the weight of the charged steel liquid in the tundish is less than the weight of the discharged steel liquid, the weight of the steel liquid in the tundish is reduced from 90-B to B, and the steel liquid is stabilized at 65-B to 80-B;
3) When the weight of the steel ladle liquid is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the steel ladle liquid is increased to a full ladle weight B; when the weight of the steel ladle molten steel is reduced to 0 percent, the opening degree of the steel ladle sliding plate is reduced to 0 percent;
(4) And (4) replacing a new ladle according to the set continuous casting furnace number, and repeating the steps (2) and (3) until the whole casting process is finished.
2. The method for extending the number of pure steel pouring furnaces based on the molten steel weight information as claimed in claim 1, comprising the steps of:
(1) Control of the 1 st ladle
1) When the weight of the 1 st ladle of molten steel is not less than 90 percent, opening a ladle sliding plate, starting to increase the opening degree of the sliding plate from 0 percent to 70-80 percent, wherein the weight of the molten steel filled in the tundish is more than that of the outflow molten steel, the weight of the molten steel in the tundish is increased, and the molten steel in the tundish is stabilized at 90 percent;
2) And reducing the weight of the molten steel in the ladle to 55-75% by A, reducing the opening of the slide plate of the ladle from 70-80% to 40-50%, reducing the weight of the charged molten steel in the tundish to less than the weight of the discharged molten steel, reducing the weight of the molten steel in the tundish from 90% to B, and stabilizing the weight of the molten steel in the tundish to 75-80% by B;
3) When the weight of the molten steel in the ladle is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the molten steel in the tundish is increased to the full ladle weight B; when the weight of the steel ladle molten steel is reduced to 0 percent, the opening degree of the steel ladle sliding plate is reduced to 0 percent;
(2) Replacement ladle
Controlling the weight of the tundish steel liquid to be not less than 50% and B-70% when the ladle slide plate for replacing the ladle is opened;
(3) Take over control of the ladle
1) Opening a sliding plate of the steel ladle, wherein the opening degree of the sliding plate is increased to 70-80% from 0%, the weight of the molten steel filled in the tundish is greater than that of the outflow molten steel, the weight of the molten steel in the tundish is increased, and the molten steel is stabilized within 90 percent to B percent;
2) After the weight of the steel ladle liquid is reduced to 55-75%, the opening of the steel ladle slide plate is reduced from 70-80% to 40-50%, the weight of the charged steel liquid in the tundish is less than the weight of the discharged steel liquid, the weight of the steel liquid in the tundish is reduced from 90-B, and is stabilized at 75-B-80-B;
3) When the weight of the steel ladle liquid is reduced to 15-30 percent, the opening degree of the steel ladle slide plate is increased from 40-50 percent to 70-80 percent, and the weight of the steel ladle liquid is increased to a full ladle weight B; when the weight of the steel ladle liquid is reduced to 0 percent, the opening degree of the steel ladle slide plate is reduced to 0 percent;
(4) And (5) replacing a new ladle according to the set continuous casting furnace number, and repeating the steps (2) and (3) until the whole casting process is finished.
3. The method for prolonging the number of pure steel pouring furnaces based on the weight information of molten steel according to claim 1 or 2, wherein the ladle change time in the step (2) is controlled to be 2-4 min.
4. The method for extending the number of pure steel casting furnaces based on the weight information of molten steel according to claim 1 or 2, wherein the weight weighing information of the molten steel of the ladle is based on a weighing system installed at a cantilever of the ladle turret.
5. The method for extending the number of pure steel pouring furnaces based on molten steel weight information according to claim 1 or 2, wherein the weight weighing information of the molten steel in the tundish is based on a weighing system installed at a frame of the tundish car.
6. The method for prolonging the number of pure steel pouring furnaces based on the weight information of the molten steel according to claim 1 or 2, characterized in that an automatic control system is adopted to collect and compare the real-time weight data of the molten steel ladles and the molten steel in the tundish and control the opening degree of corresponding steel ladle sliding plates.
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Citations (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8333127D0 (en) * | 1982-12-14 | 1984-01-18 | Nippon Kokan Kk | Rotary nozzle |
| US4498611A (en) * | 1982-03-05 | 1985-02-12 | Nippon Kokan Kabushiki Kaisha | Dual door type rotary nozzle |
| US4865234A (en) * | 1987-03-26 | 1989-09-12 | Asea Brown Boveri Ab | Pouring control device |
| JPH0550203A (en) * | 1991-08-27 | 1993-03-02 | Kobe Steel Ltd | Device for controlling weight of molten steel in tundish in continuous casting |
| CN1282281A (en) * | 1997-10-31 | 2001-01-31 | 日本钢管株式会社 | Apparatus for controlling amount of teeming molten metal and slide plate used for the same |
| KR20010057306A (en) * | 1999-12-21 | 2001-07-04 | 신현준 | The estimate method of tundish weight on casting |
| JP2003145257A (en) * | 2001-11-09 | 2003-05-20 | Shinkawa Denki Kk | Method for judging completion in pouring of molten steel and judging instrument therefor |
| JP2003164951A (en) * | 2001-11-27 | 2003-06-10 | Nippon Steel Corp | Weight control method for molten steel in tundish during continuous casting |
| WO2003092928A1 (en) * | 2002-04-27 | 2003-11-13 | Sms Demag Aktiengesellschaft | Method and device for the weight-controlled filling of ingot molds in non-iron casting machines |
| CN102851443A (en) * | 2012-09-19 | 2013-01-02 | 武汉钢铁(集团)公司 | Method for increasing continuous casting heats of aluminum-deoxidized bearing steel |
| CN104999043A (en) * | 2014-04-17 | 2015-10-28 | 宝山钢铁股份有限公司 | Online measuring device and method for opening degree of sliding nozzle of continuous casting ladle |
| CN105983673A (en) * | 2015-02-28 | 2016-10-05 | 宝山钢铁股份有限公司 | Continuous casting ladle final casting control system based on ladle discharged slag detection system and process control method |
| CN106541122A (en) * | 2015-09-17 | 2017-03-29 | 鞍钢股份有限公司 | Method for preventing slag entrapment of tundish |
| CN106623887A (en) * | 2016-11-21 | 2017-05-10 | 张家港联峰钢铁研究所有限公司 | Ladle filler sand discharging device and continuous casting ladle casting method |
| KR101761144B1 (en) * | 2016-01-19 | 2017-07-25 | 태인시스템주식회사 | Method for Detecting Slag employed in Appliance for producing Iron |
| CN107398538A (en) * | 2016-05-20 | 2017-11-28 | 上海梅山钢铁股份有限公司 | Become the decision method that steel grade cast continuous casting billet mixes steel region |
| CN107790665A (en) * | 2017-10-31 | 2018-03-13 | 首钢京唐钢铁联合有限责任公司 | Automatic control method and system for liquid level of tundish |
| CN107824756A (en) * | 2016-09-15 | 2018-03-23 | 上海梅山钢铁股份有限公司 | Steel control method more than a kind of slab caster tundish based on continuous temperature measurement |
| JP2018066030A (en) * | 2016-10-17 | 2018-04-26 | 新日鐵住金株式会社 | Manufacturing method of high cleanliness steel |
| CN108555262A (en) * | 2018-05-23 | 2018-09-21 | 洛阳理工学院 | A kind of tundish method for automatic controlling liquid level and system |
| CN108637199A (en) * | 2018-06-04 | 2018-10-12 | 东北大学 | The method for pouring the first stove ladle molten steel temperature is unwrapped among a kind of reduction |
| CN109158567A (en) * | 2018-09-30 | 2019-01-08 | 武汉钢铁有限公司 | Continuous casting production even pours process constant liquis position control method |
| CN110064741A (en) * | 2019-06-10 | 2019-07-30 | 成渝钒钛科技有限公司 | Continuous cast crystallizer number lift technique in steel-making continuous casting |
| CN110216260A (en) * | 2019-06-19 | 2019-09-10 | 武汉钢铁有限公司 | The method of Cleanliness of Molten Steel is improved in continuous casting process |
| CN111250672A (en) * | 2018-11-30 | 2020-06-09 | 上海梅山钢铁股份有限公司 | Continuous casting ladle final pouring method based on steel passing amount comparison |
| CN111719037A (en) * | 2019-03-21 | 2020-09-29 | 本钢板材股份有限公司 | Method for increasing number of continuous casting furnaces of double-flow plate blank tundish |
| CN112008048A (en) * | 2019-05-28 | 2020-12-01 | 宝山钢铁股份有限公司 | Method for measuring slag discharge of continuous casting ladle |
| CN112059127A (en) * | 2019-06-11 | 2020-12-11 | 宝山钢铁股份有限公司 | Continuous temperature measuring device for tundish molten steel |
| CN112139467A (en) * | 2019-06-28 | 2020-12-29 | 宝山钢铁股份有限公司 | Water gap action control method based on prolonging service life of sliding water gap |
| CN112276070A (en) * | 2020-10-16 | 2021-01-29 | 联峰钢铁（张家港）有限公司 | Automatic tundish weight regulating and controlling method |
-
2021
- 2021-03-29 CN CN202110333387.2A patent/CN115138832B/en active Active
Patent Citations (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4498611A (en) * | 1982-03-05 | 1985-02-12 | Nippon Kokan Kabushiki Kaisha | Dual door type rotary nozzle |
| GB8333127D0 (en) * | 1982-12-14 | 1984-01-18 | Nippon Kokan Kk | Rotary nozzle |
| US4865234A (en) * | 1987-03-26 | 1989-09-12 | Asea Brown Boveri Ab | Pouring control device |
| JPH0550203A (en) * | 1991-08-27 | 1993-03-02 | Kobe Steel Ltd | Device for controlling weight of molten steel in tundish in continuous casting |
| CN1282281A (en) * | 1997-10-31 | 2001-01-31 | 日本钢管株式会社 | Apparatus for controlling amount of teeming molten metal and slide plate used for the same |
| KR20010057306A (en) * | 1999-12-21 | 2001-07-04 | 신현준 | The estimate method of tundish weight on casting |
| JP2003145257A (en) * | 2001-11-09 | 2003-05-20 | Shinkawa Denki Kk | Method for judging completion in pouring of molten steel and judging instrument therefor |
| JP2003164951A (en) * | 2001-11-27 | 2003-06-10 | Nippon Steel Corp | Weight control method for molten steel in tundish during continuous casting |
| WO2003092928A1 (en) * | 2002-04-27 | 2003-11-13 | Sms Demag Aktiengesellschaft | Method and device for the weight-controlled filling of ingot molds in non-iron casting machines |
| CN102851443A (en) * | 2012-09-19 | 2013-01-02 | 武汉钢铁(集团)公司 | Method for increasing continuous casting heats of aluminum-deoxidized bearing steel |
| CN104999043A (en) * | 2014-04-17 | 2015-10-28 | 宝山钢铁股份有限公司 | Online measuring device and method for opening degree of sliding nozzle of continuous casting ladle |
| CN105983673A (en) * | 2015-02-28 | 2016-10-05 | 宝山钢铁股份有限公司 | Continuous casting ladle final casting control system based on ladle discharged slag detection system and process control method |
| CN106541122A (en) * | 2015-09-17 | 2017-03-29 | 鞍钢股份有限公司 | Method for preventing slag entrapment of tundish |
| KR101761144B1 (en) * | 2016-01-19 | 2017-07-25 | 태인시스템주식회사 | Method for Detecting Slag employed in Appliance for producing Iron |
| CN107398538A (en) * | 2016-05-20 | 2017-11-28 | 上海梅山钢铁股份有限公司 | Become the decision method that steel grade cast continuous casting billet mixes steel region |
| CN107824756A (en) * | 2016-09-15 | 2018-03-23 | 上海梅山钢铁股份有限公司 | Steel control method more than a kind of slab caster tundish based on continuous temperature measurement |
| JP2018066030A (en) * | 2016-10-17 | 2018-04-26 | 新日鐵住金株式会社 | Manufacturing method of high cleanliness steel |
| CN106623887A (en) * | 2016-11-21 | 2017-05-10 | 张家港联峰钢铁研究所有限公司 | Ladle filler sand discharging device and continuous casting ladle casting method |
| CN107790665A (en) * | 2017-10-31 | 2018-03-13 | 首钢京唐钢铁联合有限责任公司 | Automatic control method and system for liquid level of tundish |
| CN108555262A (en) * | 2018-05-23 | 2018-09-21 | 洛阳理工学院 | A kind of tundish method for automatic controlling liquid level and system |
| CN108637199A (en) * | 2018-06-04 | 2018-10-12 | 东北大学 | The method for pouring the first stove ladle molten steel temperature is unwrapped among a kind of reduction |
| CN109158567A (en) * | 2018-09-30 | 2019-01-08 | 武汉钢铁有限公司 | Continuous casting production even pours process constant liquis position control method |
| CN111250672A (en) * | 2018-11-30 | 2020-06-09 | 上海梅山钢铁股份有限公司 | Continuous casting ladle final pouring method based on steel passing amount comparison |
| CN111719037A (en) * | 2019-03-21 | 2020-09-29 | 本钢板材股份有限公司 | Method for increasing number of continuous casting furnaces of double-flow plate blank tundish |
| CN112008048A (en) * | 2019-05-28 | 2020-12-01 | 宝山钢铁股份有限公司 | Method for measuring slag discharge of continuous casting ladle |
| CN110064741A (en) * | 2019-06-10 | 2019-07-30 | 成渝钒钛科技有限公司 | Continuous cast crystallizer number lift technique in steel-making continuous casting |
| CN112059127A (en) * | 2019-06-11 | 2020-12-11 | 宝山钢铁股份有限公司 | Continuous temperature measuring device for tundish molten steel |
| CN110216260A (en) * | 2019-06-19 | 2019-09-10 | 武汉钢铁有限公司 | The method of Cleanliness of Molten Steel is improved in continuous casting process |
| CN112139467A (en) * | 2019-06-28 | 2020-12-29 | 宝山钢铁股份有限公司 | Water gap action control method based on prolonging service life of sliding water gap |
| CN112276070A (en) * | 2020-10-16 | 2021-01-29 | 联峰钢铁（张家港）有限公司 | Automatic tundish weight regulating and controlling method |
Non-Patent Citations (3)
| Title |
|---|
| 任宏伟;: "提高双流板坯中间包连浇炉数技术研究", 本钢技术, no. 04 * |
| 李源源;覃强;韦军尤;陈永金;周汉全;江学德;: "影响IF钢连浇炉数的因素及改进措施", 柳钢科技, no. 06 * |
| 罗利华;佐祥均;: "连铸过程中小方坯中间包钢水液位控制的研究", 连铸, no. 04 * |
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